( clxxxix ) 



both Bomhus and Apis are offshoots ; (6) the $ $ o^ both the 

 latter Genera have inherited the imperfect structure of the 

 cJ cj in the parent-stock ; (c) the ? of Borahus has retained the 

 complete structure, and transmits it to her Worker offspring ; 

 and {d) the $ of Apis has ceased to develop it in herself, but 

 retains it as a latent chai'acter, since she transmits it to her 

 offspring. 



The legs of $ and ^ Ants and Wasps show no striking 

 characters. Their sole use seems to be for locomotion, and 

 if modified at all (as by abnormal elongation) the advantage 

 gained no doubt is simply speed. But in Fossors the $ legs 

 are often evidently indicative of their habits. Species which, 

 like Pompilids, fly little, but run and skip over herbage in 

 pursuit of wingless prey (spiders, etc.), which they afterwards 

 drag into their burrows, often have the legs (especially the 

 hind-pair) i^emarkably elongated. Others which prey on 

 flying or leaping victims (Diptera, small Lepidoptera, Ortho- 

 pterous and Hemipterous "nymphs," or even other Hymeno- 

 ptera), fly more, and run less, both in seeking and bearing 

 home their prey. In such (e. g. Bembex, Tachytes, Oxyhelus, 

 Astata, etc.) the legs are mostly short, but stout and armed 

 with many short stiff spines which may act perhaps as grap- 

 pling-instruments. Again, practically all Fossorial $ 9 have 

 much work to do in clearing sand, sawdust, and debris of 

 all kinds, out of their burrows ; and many of them are 

 assisted in this work by possessing a sort of "rake" of long 

 subequal spines (called the " pecten ") on their front-tarsi ; 

 and other spines, or serrations, or rasp-like denticulations, on 

 the hind-tibiae especially, but also on these and other parts of all 

 the legs. Amniophila ? ? at work can be seen to carry out 

 armfuls (as it were) of sand; and wood-boring Crahronidae 

 kick out backwards a sti-eam of fine sawdust, as they penetrate 

 into a stump or a paling. Thus, in one Avay or other, all 

 these leg-characters in the ^ ? seem accommodated to maternal 

 industries ; and if present (as sometimes happens) in the $ $, 

 are attributable, probably, either to Inheritance simply, or 

 to Transmission, or to Adaptation for Pairing. 



(4) The $ abdomen presents few conspicuous Sexual 

 characters in Aculeates of any kind. Its dorsal apex will 



